This invention pertains to the field of internal combustion engines. Presently, the internal combustion engines being manufactured generally suffer from a plethora of problems, such as excessive weight and size, low efficiency, low power-to-weight ratio, low torque, high fuel consumption, high levels of air pollution, excessive noise and vibration, high complexity and large number of parts, which leads to decreased reliability and durability of the engine. The present invention endeavors to solve these problems to some extent, improving the relevant parameters substantially.